One boring day during a xmas holiday a while ago I started putting together a Tesla coil, and here's what I've made so far..

 

Here's my basic setup as of now. Using a rather small but functional spherical discharge terminal. I'm working on getting sparks from larger toroid DCTs but when these pictures were taken this was the best my system could do.

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 Here I've placed a small metal ball on top of the main discharge sphere. Note the neat corona around the joint between the two hemispheres of the DCT.

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Yeah, even up here in Sweden we're sent piles and piles of those damned Compuserve and AOL CDs. And this is what I do with 'em. First the disc is micro waved at full power for a couple of seconds, to create small cracks in the metal layer. Then the disc is placed on the discharge terminal and -bzzt- all the little cracks light up and sparks fly from around the edge. 

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On this picture I've placed an ordinary light bulb on top of the DCT. The discharges emanate from the wire inside the bulb and then exit through the glass, showing off a decent banjo effect. 

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4 Klinger Neon sign transformers rated 3,75 kV 50mA each. All wired in series and fed 230V 50 Hz via a sturdy radio noise filter.

 

6 flat plate, oil filled, polyethene capacitors wired in parallel (stupid I know, I should've gone for the series approach). Total capacitance as of now:  ca 0,009 uF.

 
 

 

RQ-style cylindrical gap with about 9 copper pipe electrodes enclosed in 11 cm dia PVC pipe, with a trusty 18W PAPST handling the ventilation.

 
   

A little over 13 turns of 1/4" soft copper pipe in a cone shaped configuration with roughly 15 degrees inclination          810 turns of 0,6 mm copper magnet wire wound on 11 cm dia PVC pipe. Plexiglas capped and thickly coated.